Unitary exhaust manifold gasket and heat shield



1960 R. H. MALCOLM 2,954,763

UNITARY EXHAUST MANIFOLD GASKET AND HEAT SHIELD Filed April 29, 1959 2Sheets-Sheet 1 A r romvzr UNITARY EXHAUST MANIFOLD GASKET AND HEATSHIELD Filed April 29, 1959 Oct. 4, 1960 R. H. MALCOLM 2 Sheets-Sheet 2ATTORNEY INVENTOR B06621 H ZZZczZwZm PM 0 United States Patent Q TUNITARY EXHAUST MANIFOLD GASKET AND HEAT SHIELD Robert H. Malcolm, FortWayne, Ind., assignor to International Harvester Company, Chicago, 111.,a corporation of New Jersey Filed Apr. 29, 1959, Ser. No. 809,827

9 Claims. (Cl. 123-198) the connections of the electrical conductingcables attached to the spark plugs which cables and spark plugs form apart of the engine ignition system, are often times adversely effectedby the heat radiated from the exhaust manifold during operation of theengine. This is especially true in heavy duty engine installations suchas those employed in motor trucks wherein the vehicle is operated forlong periods of time under maximum load conditions. It has been foundthat the heat radiated from the exhaust manifold often times is of suchintensity as to contribute to the failure of the ignition system bydeteriorating the cable insulation and the mechanical and electricalconnections of the cables to the spark plugs. It is, therefore, aprimary objective of the present invention to mitigate the damaginginfluence of the heat radiating from the exhaust manifold on theignition system cables and the mechanical and electrical connectionsthereof to the spark plugs by providing a protective heat shield orbaflie spaced between the exhaust manifold and the spark plugs.

A further object is the provision of an exhaust manifold gasket having aheat shield incorporated therein for preventing the ignition systemcables and the connections thereof with the spark plugs from overheating.

A still further object is the provision of a unitary exhaust manifoldgasket and protective heat shield which is simple and durable inconstruction, economical to manufacture and which does not interfere inany way with the normal operation of the engine in which it isincorporated.

Still another object of the invention is to provide a protective heatshield which is attached to the engine when the exhaust manifold isassembled on the engine and which does not interfere with the removal,replacement or adjustment of the spark plugs.

The foregoing and other important objects and desirable featuresinherent in and encompassed by the invention together with many of thepurposes and uses thereof will become readily apparent from a reading ofthe ensuing description in conjunction with the annexed drawings inwhich: 7

Figure 1 is a side elevational View of an internal combustion engineembodying the invention;

Figure 2 is a sectional view taken substantially along line 22 of Figure1;

Figure 3 is an enlarged top plan view of the unitary exhaust manifoldgasket and heat shield detached from the engine;

Figure 4 is a bottom plan view of the unitary exhaust manifold and heatshield;

Patented Oct. 4, 1960 Figure 5 is. a sectional view taken substantiallyalong line 55 of Figure 4; and

Figure 6 is a fragmentary sectional view taken substantially along line6-6 of Figure 4.

Referring to the, drawings in detail wherein like reference charactersrepresent like elements throughout the various views, there is partiallyshown a conventional V-type internal combustion engine 10 which includesa cylinder block 11 having two rolls of cylinders 12, only one of whichis shown in the drawings, arranged at an angle with respect to eachother. Secured to each roll or bank of cylinders 12. is a cylinder head13. A piston 14 is reciprocal in each cylinder 12 and the top of thepiston and the surface 15 on the underside of the cylinder head 13 inalignment therewith form a combustion chamber 16. The cylinder head 13is provided with an air fuel intake passageway 17 which has one end incommunication with the combustion chamber 16 and its opposite end incommunication with an intake manifold 18. ,An intake valve 19 controlsthe flow of charge from the intake manifold 18 to the combustion chamber16 in a conventional manner. A plurality of spark plugs 20 are threadedinto recesses formed through the cylinder head 13 and each spark plughas its electrode disposed within a respective combustion chamber 16 forigniting the air fuel charge within the combustion chamber. The abovedescribed engine structure is conventional and forms no part of thepresent invention. The hot prodnets of combustion are emitted from thecombustion chamber 16 through passageways provided in the cylinder head13 which are in communication with an exhaust manifold 21.

Releasably attached to the outer terminal end of each spark plug 20 is ahigh tension cable 22. The opposite end of the high tension cables 21are connected with the engine electrical ignition system distributor(not shown) in an old and well known manner. Each high tension cable 22comprises a metallic conductor or wire molded or otherwise embedded in asheathing or cover 24. The ends of the cables 22 are provided withenlarged contacts 25. Each cable 22 is attached to the respective sparkplug 20 by means of a substantially tubular connector 26 whichfrictionally grips the outer covering 24 of the cable 22 and the outerterminal end of the spark plug 20. The connectors 26 are sufficientlyflexible to tightly embrace the outer covering 24 of the cable and theterminal end of the spark plug 20 to maintain a good electrical contactbetween the enlarged contact 25 and the tip portion 27 of the spark plugouter terminal as shown in Figure 2. The connectors 26 maintain theelectrical contact between the contacts 25 and the tips 27 of the sparkplugs 20 and such electrical contacts are protected from theirdeleterious effects of dust, dirt and oil. Of necessitythe connectors 26and the outer casing 24 of the cables 22 are made of material such asrubber or other material having like physical characteristics which isincapable of conducting electric current and is flexible to a certaindegree without being broken, cracked or distorted. It is well known thatsuch materials when subjected to over heating for long periods of timetend to become brittle and crack and lose their resiliency as well astheir electrical insulating properties. When this occurs the connectors26 lose their ability to maintain the contacts 25 firmly into engagementwith the tips 27 of the spark plugs 24), and the dielectriccharacteristics of the insulating covers 24 of the cables 22 and theconnectors 26 deteriorate and lose their ability to prevent electricalleakage to the surrounding metal parts of the engine with the resultthat the engine ignition system is adversely effected and functionsimproperly. In order to obviate these difficulties, the presentinvention contemplates the provision of a unitary exhaust manifoldgasket and heat shield, shown in Figures 3 and 4. A generally flatelongated section 28 of the unitary exhaust manifold gasket and heatshield is provided with a plurality of spaced openings 29 therethronghencircled by an embossment 30 as in conventional exhaust manifoldgaskets. The flat section 28 as well as the heat shield, designatedgenerally by numeral 31, of the unitary exhaust mamfold and heat shield,is made of sheet metal or the like as used to. construct conventionalintake exhaust manifold gaskets. One side of the section 28 is adaptedto bear against a flat surface 32 formed on the cylinder head 13 withthe openings 29 in registration with exhaust passageways (not shown)leading from the combustion chambers 16 and opening into the surface 31.As in conventional engine installations, the exhaust manifold 21 ismounted on the surface 32 of the cylinder head 13 with the fiat section28 sandwiched thereinbetween. The cored passageways formed in theexhaust manifold 21 are in communication with the openings 29 in thesection 28 and the exhaust passageways formed in the cylinder head 13for conveying the hot products of combustion to the atmosphere. It isbelieved obvious that during operation of the engine heat is radiatedfrom the exhaust gases flowing through the exhaust manifold 21 and,because of the close proximity of the spark plug terminals 27,connectors 26, and the ends of the cables 22 to the exhaust manifold,there is a tendency for the sheathing 24 and the connectors 26 tooverheat and deteriorate. The heat shield or baffie 31 is integrallyformed with and extends from one longitudinal edge of the flat section28. As best shown in Figure 2, the major portion of the heat shield 31lies substantially in a plane angularly disposed With respect to theplane of the flat section 23 and when the unitary exhaust manifold andheat shield is mounted in position the major portion of the heat shield31 is spaced from and overlies the uppermost surface of the exhaustmanifold 21. Integrally formed with and extending angularly from thegeneral plane of the major portion of the shield 31 are a pair of spacedcars 32 which, in turn, have substantially flat tabs 33 formed on thefree ends thereof. The tabs 33 lie in a plane substantially parallel andspaced from the flat gasket section 28 and each tab 33 is provided withan aperture 34 which is in vertical alignment with a respective aperture35 formed in the flat section 28. Each tab 33 is also provided with anelongated slot 36 spaced from the aperture 34 formed therein for apurpose which will be explained hereinafter. Each cored passagewayformed in the exhaust manifold 21 has an end thereof defined by aperipheral flange 37, a portion of such flange 37 being shown in Fig. 2.The flanges 37 are provided with a flat surface 38 which bears againstthe fiat section 28 of the unitary exhaust manifold gasket andheat'shield. The manifold 21, as in the construction of conventionalexhaust manifolds for V-type internal combustion engines, is providedwith enlarged bosses 39 on each end thereof. An attaching bolt 40extends through a central bore formed in each boss 39 and is threadedinto a threaded recess formed in the cylinder head 13. The attachingbolt 40 also extends through an aperture formed in an L-shapcd lockwasher 41 which is compressed between the head 42 of the bolt and theboss 39' when the bolt 40 is drawn up tightly. The short leg 43 of thelock washer 41 bears against a flat surface 44- of the boss 39, as bestshown in Fig. 2. Once the bolts 40 are drawn up properly the free endportion 45 of the longer leg of the lock washer 41 is bent substantially90 to engage a flat on the head 42 of the bolt 41. Thus the bolts 4% areprevented from unthreading from the threaded recesses formed in thecylinder head 13 during operation of the internal combustion engine 10.A mid portion 46 of the exhaust manifold 21 is in the form of asubstantially fiat flange having an opening extending therethroughadapted to register with an aperture 47 formed in the fiat gasketsection 28 of the unitary exhaust manifold gasket and heat shield whenthe section 28 is correctly positioned on the cylinder head surface 32.An attaching bolt 48 extending through the opening and the aperture 47into a threaded recess formed in the cylinder head 13 is utilized toclamp the mid portion 46 of the exhaust manifold 21 to the cylinder head13. A lock washer 49, similar to the lock washers 41 describedhereinabove, is employed to prevent unthreading of the attaching bolt 48from its mating recess in the cylinder head 13. The exhaust manifold 21is also provided with a pair of enlarged, integrally-formed cylindricalbosses 5G, each of which is spaced substantially midway between arespective end boss 39 and the flange 46. With the unitary exhaustmanifold gasket and heat shield correctly in place on the internalcombustion engine 10 each tab 33 overlies the flat outer end of arespective boss 51'}, as shown in Fig. 2, with the aperture 34 thereofin registration with a central bore formed through the boss 50. Eachcentral bore is also in alignment with a respective aperture 35.Extending through each aperture 34 and the aperture. 35 associatedtherewith and the central bore of a respective boss 50 is an attachingbolt 51 which is threaded into a recess formed in the cylinder head 13.An L-shaped lock washer 54 is interposed between the head 52 of eachattaching bolt 51 and the outer surface of the tab 33 with therelatively shorter leg 53 thereof projecting through a respective slot36. The free portion 55 of the relatively longer leg of the lock washer54 is bent upwardly away from the tab 33 to bear against a fiat surfaceof the bolt head 52 to prevent unthreading of the bolt 51.

From the foregoing, it will be appreciated that the unitary exhaustmanifold gasket and protective heat shield not only function as a gasketfor sealing the joint be tween the exhaust manifold and the cylinderhead but also as a protective heat shield to prevent the connectors 26and the insulating cover 24 of the cables 22 from overheating which issimple and durable in construction, economical to manufacture andassemble on the engine and which does not interfere in any way with theoperation of the engine.

The embodiment of the invention chosen for the purposes of illustrationand description herein is that preferred for achieving the objects ofthe invention and developing the utility thereof in the most desirablemanner, due regard being had to existing factors of economy, simplicityof design and construction, and the improvements sought to be effected.It will be appreciated, therefore, that the particular structural andfunctional aspects emphasized herein are not intended to exclude, butrather to suggest other adaptations and modifications of the inventionas fall within the spirit and scope of the invention as defined in theappended claims.

What is claimed is:

1. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethrough in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electrical ignition system including a plurality of sparkplugs attached to said cylinder head adjacent a longitudinal edge ofsaid flat surface and a plurality of electrically insulated, electriccurrent conducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespetive spark plug; a unitary exhaust manifold heat shield including aflat gasket section interposed between said exhaust manifold and saidcylinder head flat surface and a heat shield integrally formed with onelonigtudinal edge of said flat gasket section extending outwardly fromsaid one longitudinal edge of said flat surface and being spaced betweensaid exhaust manifold and spark plug terminals and cable ends, said heatshield including a pair of longitudinally spaced tabs lyingsubstantially in a plane parallel to the plane of said flat gasketsection; and means for attaching said exhaust manifold to said cylinderhead including a plurality of attaching bolts, certain of said boltsextending through said tabs and said fiat gasket section.

2. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethrough in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electrical ignition system including a plurality of sparkplugs attached to said cylinder head adjacent a longitudinal edge ofsaid fiat surface and a plurality of electrically insulated, electriccurrent conducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespective spark plug; a unitary exhaust manifold heat shield includinga flat gasket section interposed between said exhaust manifold andcylinder head flat surface and a heat shield integrally formed with onelongitudinal edge of said flat section extending away from said onelongitudinal edge of said flat surface and being spaced between saidexhaust manifold and spark plug terminals and cable ends; and means forattaching said exhaust manifold to said cylinder head including aplurality of attaching bolts, certain of said bolts extending throughsaid heat shield and said flat gasket section.

3. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethrough in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electrical ignition system including a plurality of sparkplugs attached to said cylinder head adjacent a longitudinal edge ofsaid flat surface and a plurality of electrically insulated, electriccurrent conducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespective spark plug; a unitary exhaust manifold heat shield includinga flat gasket section interposed between said exhaust manifold and saidcylinder head flat surface and an integrally formed heat shieldextending from one longitudinal edge of said flat section and beingspaced between said exhaust manifold and spark plug terminals and cableends; and means for attaching said exhaust manifold to said cylinderhead, said means also serving to attach said unitary exhaust manifoldheat shield to said cylinder head.

4. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethrough in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electrical ignition system including a plurality of sparkplugs attached to said cylinder head adjacent a longitudinal edge ofsaid flat surface and a plurality of electrically insulated, electriccurrent conducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespective spark plug; a heat shield extending from said longitudinaledge of said flat surface and being spaced between said exhaust manifoldand spark plug terminals and cable ends; and means for attaching saidmanifold to said cylinder head, said means 1allso serving to attach saidheat shield to said cylinder ead.

5. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethro-ugh in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electric ignition system including a plurality of spark plugsattached to said cylinder head adjacent a longitudinal edge of said flatsurface and a plurality of electrically insulated, electric currentconducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespective spark plug; a heat shield extending from said longitudinaledge of said flat section and being spaced between said exhaust manifoldand spark plug terminals and cable ends; and means for attaching saidheat shield to said cylinder head.

6. In an internal combustion engine having a cylinder head provided witha substantially flat surface; an exhaust manifold mounted on said flatsurface having passages therethrough in communication with the interiorof said cylinder head for conducting hot products of combustion from theengine; an electrical ignition system including a plurality of sparkplugs attached to said cylinder head adjacent a longitudinal edge ofsaid flat surface and a plurality of electrically insulated, electriccurrent conducting cables, each of said cables having an end thereofelectrically and mechanically connected to the outer terminal of arespective spark plug; a heat shield spaced between said exhaustmanifold and spark plug terminals and cable ends; and means forattaching said heat shield to said cylinder head.

7. For use with an internal combustion engine, an exhaust manifoldgasket having a heat shield integrally formed therewith.

8. For use with an internal combustion engine, a substantially flat,generally rectangular exhaust manifold gasket section, and a heat shieldintegrally formed with and extending angularly from one longitudinaledge of said gasket section.

9. For use with an internal combustion engine, a substantially flat,generally rectangular exhaust manifold gasket section, and a heatshield, said heat shield comprising a body of thin-walled materialintegrally formed with and extending angularly from one longitudinaledge of said gasket section.

References Cited in the file of this patent UNITED STATES PATENTS1,491,361 Reddig Apr. 22, 192.4 1,994,614 Lansing Mar. 19, 1935

